Automatic tuner



Feb. 29, 1944. B A SCHWARZ ET A| 2,342,902

AUTOMATIC TUNER Filed Aug. 3, 1959 4 Sheets-Sheet 1 [75 Inventors Gttornegs Feb. 29, 1944. a. A. scHwARz Erm. 2,342,902

AUTOMATIC TUNER Filed Aug. 5, 1939 4 Sheets-Sheet 2 Feb 29, 1944 B. A. SCHWARZ ETAI.

AUTOMATIC TUNER Filed Aug. 5, 1959 4 Sheets-Sheet 3 NQ @h mm. l

.mb x mb s ma Feb 29, 1944- B. A. SCHWARZ :TAL 2,342,902

AUTOMATIC TUNER Filed Aug. 3, 1939 4 Sheets-Sheet 4 n CLUTCH i? y /75 %w y Gttoxnegs Patented Feb. 29, 1944 2148.902 AUTOMATIC TUNER liertramaisehwanandlmdwig aneignen J. Fichier, Ko- Corpohomo inl.. to General Motors ration. lmtrolt.4 Mich., a corporation or Dela- Appllcltlcn Allglllt 8, 1939, Sedll No. 288,201

(Cl. 'I4-10) Claim This invention relates to automatic indexing means and more specifically to automatic indexlng mechanism for automatically tuning a radio communication device.

It has been round that certain persons. particularly children, have dimculty tuning radio receivers accurately and this invention provides push-button operated tuning means which enables one to quickly and accurately tune a radio receiver. This type of mechanism is found to be particularly useful for tuning radio receivers installed on automotive vehicles where the driver must give constant attention to steering as well as all the other duties connected with the safe operation o! the vehicle.

Prior devices of this nature have been constructed .as accessories to be added to conventional radio receivers which have made them unsightly in appearance and constructed so that they interfere with the operating controls on the automobile due to their size.

One of the objects of the present invention is to provide adjustable automatic indexing control mechanism in which any one of a plurality of radio stations may be sharply tuned by one-way movement of one oi a plurality oi buttons conveniently located with reference to both the operator and the radio receiver.

Another object of the present invention is to provide a simple but eiiicient indexing mechanism mounted on part of the housing which encloses it and also the radio receiver so that the complete assembly may be mounted in a small space l out o! the way of the control mechanism necessary to safe operation of the vehicle.

Another object o! our invention is to provide a self-contained illuminating system 4for indicator mechanism associated with the automatic and conventional tuning control mechanism provided.

A still further object of the invention is to provide automatic mechanism associated with the automatic tuning means which renders the conventional tuning mechanism ineil'ective when the automatic tuning mechanism is in operation.

These and other objects will be best understood by reference to the following speclncation and claims. together with the accompanying drawings, in which:

Figure 1 is a front elevation o! the control panel oi' the device.

Figure 2 is a top plan view, partly in broken horizontal section, o! the control device.

Figure 3 is a side sectional view taken on line I-l oi Figure 2.

Figure 4 is a side elevational view with some ot the parts shown in vertical section and others Vbroken away to show certain structural details.

Figure 5 is a side elevational view with parts broken away to show details of the associated electrical control mechanism.

Figure 6 is an enlarged side elevation view similar to Figure 4 with some of the parts broken away further to show additional structural details.

Figure 'l is a top plan view showing the lighting arrangements associated with the device with some of the parts thereof broken away.

Figure 8 is a side sectional view taken on line l-l of Figure 2.

Figure 9 is a side sectional view taken on line 1-1 ofFlgure-2.

Figure 10 is a schematic wiring diagram showing the circuit connections .between the electrical devices associated with the control device.

Figures 11 and 12 are perspective views of details oi the device.

Referring now to Figure 2 of the drawings, a tuning shaft I is mounted for rotary movement in thrust bearings. not shown, in a subirame 3. An adjusting screw and locknut indicated at 5 provides a means for adjusting these bearings in the frame 3. Rotary movement of the shaft l varies the characteristics oi' an electrical device in the tuning circuit of a radio communication device by varying either the capacity, inductance or resistance oi' the circuit.

The subframe l is supported on and insulated from a die-cast subframe 1 by three resilient. non-conducting bushings l extending through spaced holes in the subirame 1. Cap screws I l threaded to the ends of the subframe 3 extend through the bushings I and serve to compress them slightly so that the frame I is insulated both mechanically and electrically from the diecast frame l.

The die-cast frame 'l is iixed to a Vertical plate Il having upper and lower horizontal extensions Il. The plate Il serves as a back plate to which vertical side plates l1 and Il are riveted. A vertical front plate Il having horizontal extensions 22 is riveted to the side plates I1 and lil to form a rectangular hollow subtrame indicated generally at 2l supporting selector mechanism to be referred to later. This subgrame 28 on which the frame members I and I are carried is supported on a pressed metal stamping 2l and is xed thereto by machine screws 21 extending upwardly through holes in the bottom of the stamping and threaded to the lower horizontal extensions il and I2 or the front and back plates I8 and II respectively, as best shown in Figure 3. The pressed metal stamping fl is formed with vertical side portions N and a vertical front face It and comprises the lower part oi a rectangular housing which encloses all the mechanism described above and about to be described together with associated apparatus not included in this application.

The control shaft I is driven by means of an insulated coupling device comprising a lever arm Il riveted to one end of the shaft land extending radially outward therefrom. The end 3| of the lever Il is bent parallel to shaft I and is reduced in width intermediate ts extremities as indicated at ll and extends through a radial slot Il in a Micarta lever Il. A helical spring clip Il placed between the end portion Il of the lever 2l and the lever Il exerts a force tending to eliminate lost motion at this point of connection. The inner end of the lever Il is attached by means of a key 4l to a collar Il and held thereon by riveting the end 4l of the collar 43. The collar I3 is ilxed to the inner end of a clutch shaft Il by a set screw It.

The clutch shaft l1 is rotatably mounted in axial alignment with the control shaft I in bearings Il and Il located in webs l2 and Il respectively in an extension Il of the die-cast subframe 'L The shaft Il is provided with an outer end portion il of reduced diameter and a radial ange portion il adjacent thereto. A brass collar 6| is supported for rotation on the shaft portion Il between the flange Il and a brass thrust collar l! which is nxed to the end of the shaft portion l1 by a set screw It. The thrust collar Il is located on the shaft inside the bearing Il. The collar I has a worm wheel Il and a brass clutch disk II fixed thereto and rotatable therewith. The clutch disk Il is provided with an annular facing 'II of resilient friction material attached to the inner radial face,

` On the other end of the shaft 41 adjacent the bearing II an iron collar 13 is fixed by a set screw 1l. This collar has a spur gear 'I1 and an iron cup-shaped member It fixed thereon. 'l'he outer annular portion of the cup member 'II is provided with an axial slot Il. A copper-plated iron clutch disk Il is located on the shaft Il between the cup member 1l and the clutch disk l.. The disk I3 is provided with an integral tongue Il bent at right angles to the disk which extends parallel to the shaft and part way into the slot Il of the cup member so that it is revolved by. but capable of axial displacement with respect to the cup member 19. The clutch disk 8l is constantly urged to theright and into engagement with the disk Il by a helical spring Il located concentricaily with respect to the shaft Il in a counterbore 01 of the collar 13.

Disengagement of the clutch disks It and Il is accomplished by the folowing structure. The annular space between the collar 1I, cut 1I, and clutch disk Il contains an annular winding II suitably insulated from these members and heid on the collar 'il by a turned-up portion II. One end Il of this winding is brought out through the slot Il in the cup 1I and soldered at Il to the gear l1 which is grounded. The other end l of this winding is brought out through aligned holes, indicated at 0l, in the gear Il and cup 'Il and is connected to a source of electrical energy by means of a switch which will4 be .described later. By this means it is evident that when the winding It is thus energiaed` a magnetic field is set up between cup Il and disk Il which will attract the disk and move it to the force of the spring 0l and engagement with the clutch disk I.

The shaft il is driven by the worm wheel l1 when the clutch elements il and il are engaged. The worm wheel4 l1 is in mesh with a worm Il located below it and supported in bearings III in a bracket III xed to the web I4 of the extension Il of the die-cast frame 1 by the machine screws Ill as best shown in Figures 2 and Il. The worm It is fixed to one end of a exible driving shaft Ill! for rotationthereby. The other end of the shaft is fixed to a manual control knob IIII supported for rotation in a bushing Il. attached to the front vertical face Il of the stamping member 2l by a nut III. Rotation of the knob III causes the shaft 41 and control shaft I to be rotated when the clutch elements Il and Il are in engagement. It will be evident that any other type of reduction gear-v ing having irreversible characteristics may be used in place of the worm wheel I1 driven by the worm Il.

The shaft Il and control shaft I may also be driven by means of the spur gear Il with the clutch elements t! and It disengaged. The gear 'l1 meshes with a spur gear 'l II having the same number of teeth as the gear 11 and is xed by means of a pin III to the end of a shaft Ill. The shaft Il! is supported in bearings lI'I and III in the side plates I1 and i9 respectively of the selector frame 23, parallel to the control shaft I and clutch shaft l1. The shaft III is provided with gear teeth intermediate the bearings iil and Il! and constitutes an elongated pinion portion III.

'Ihe shaft III is limited for movement angularly by a pin I2! pressed in a hole I!! extending diametrically through the end of the shaft III which extends through the bearing II1. The end oi' the rpin I Il is arranged to contact abutments Ill and |28 integral with the side plate lr of ene selector frame :s in either of its extreme angular positions. The abutments |21 and I2! are formed by punching and turning portions of the side plate Il outward at right angles thereto. The faces of these abutments are parallel to a vertical line extending through the center 'of the shaft IIS as best-shown in Figure 5.

The following mechanism is provided to indicate the angular position'of the shafts I, 41 and III. A pointer III is nxed to a crosshead Il! slidably mounted on a horizontal guide member Il 'l located adjacent the vertical front face Il of the metal Vhousing member 2B and nxedthereto by the brackets |34 and machine screws I" as best shown in Figures l, 2 and 6. A diecast member I". located in an openingin the front face Il of the housing adjacent to the crosshead and guide members. has a vertical flangev III through which the machine screws Ill and rivets I extend into the face Il of the housing for holding this die-cast member Ill to the housing 2i. The die-cast member is provided with an' opening III in its front vertical face which is closed' by a glass plate I having a calibrated scale Ill painted on its back face adjacent the top edge and a painted surface Ill on the back face adjacent the lower edge. `The painted surface I is located below the lower edge oi' the opening Il! adjacent a horizontal nange lli ofthe housing Ill. The glass plate Ill is held in this position by va clamp member III provided with a painted front portion |55 and is fixed to the housing |31 by machine screws |51 as best shown in Figure 6. The pointer |3| extends outwardly from the crosshead |33 and passes through the opening between the lower edge of the clamp |53 and the upper surface of the flange |5| and is bent upward so that its end |32 is located between the back surface of the glass |43 and the painted portion |55 on the front surface of the clamp |53. The end |32 of the pointer |3| has its upper extremity located adjacent the lower edge of the scale |41 and is painted white.

The following mechanism is provided to move the crosshead |33 linearly along the guide member |35 so that the position of the pointer end |32 with respect to the scale |41 indicates the angular position of the control shaft A belt |53 is fixed to the crosshead at 13| and extends horizontally from this point, passing over a pulley |33 carried on one end of the guide member |35 and around a driving pulley |35 located adjacent the spur gear ||I and fixed by means of a set screw |31 to the shaft ||5. The belt continues around the driving pulley |35 and thence around a pulley |33 located on the guide member |35 directly below and at an angle to the pulley |33 and then horizontally across and around a pulley |1| located on the opposite end of the guide member |35 and then back to the point of attachment |3| on the crosshead |33.

'Ihe die-cast member |31 is provided with a plurality of vertical ribs |13 extending between the horizontal flange |5| below the dial opening |33 and the lower vertical mounting flange |4| dividing this lower portion into ve sections (see Figures l, 2 and 4) in which are located five selector push buttons indicated at |15. These buttons are connected to adjustable mechanismscapable of revolving the shaft ||5 in either direction to a plurality of predetermined angular positions which will be described later. The selector buttons are molded of plastic material and are best shown in Figures 1, 6 and l2. In the front face of each an opening |11 is provided through which may be observed broadcasting station identification tags |13. These tags |13 are made of translucent material and these, together with a transparent cover |3| and a Lucite backing strip |33, are located in a substantially vertical slot |35 extending part way down from the upper surface of the button.

The tags |13 and painted scale are indirectly luminated by a miniature incandescent bulb |31 supported in and having one terminal grounded to a metal tube |33. The tube is provided with a central opening |3| in the wall adjacent the back of the die-cast housing |31. The tube |33 is supported in a horizontal position in the housing by brackets |33 fixed to the sides 24 of the housing 25. Bushings extend through openings in the sides 24 of the housing and into the ends of the tube |33. One of these bushings has a central opening |35 through which extends an' insulated conductor |31 which is connected to the other terminal of the bulb |31. When this conductor is connected to a source of current the light from the bulb is reflected oi! the interior surface of the tube |33 which may be painted white and passes out through the opening |3| and falls on the painted surface |43 on the back of the glass |45. Part of this light passes through the glass directly below the painted surface |43. The lower edge and a portion of the front face adjacent thereto of the glass |45 is painted and the light passing through the glass strikes the painted surfaces and by internal reflection illuminates the painted figures of the scale |41. Part of the light rays from the bulb are reflected oi! the minted strip |43 of the glass and strike the painted front surface of the clamp |53 from which they are reflected onto the painted end |32 of the pointed |3| and the space adjacent thereto, thus illuminating the needle directly and in silhouette. Rays from the bulb also pass through openings |52 in the flange |5| and fall on the upper edges oi' the Lucite strips |33 in the buttons |15 from which they are internally reflected and thus illuminate the translucent tags |13. 'The top and bottom edges of the glass |45 and Lucite strips |33 and the back surface of the tags |13 may be painted any given color so that both the figures on the glass and the tags will be illuminated by light or the color selected.

In addition to the manual control knob |31 and connecting means for rotating the control shaft through an arc of substantially degrees, adjustable indexing mechanisms operated by the selector push buttons are provided. These mechanlsms provide a means for rotating the control shaft in either direction to a plurality of preselected angular positions. Five such mechanisms are shown which provide a tuning means for a radio communication device so that any one of five wave lengths may be obtained by simply pushing on the proper selector button. Any number of these buttons may be provided and each acts on a separate connecting means made up of identical parts. Any one button in combination with its adjustable connecting means is capable of rotating the shaft II5 in either direction to a plurality of angular positions so that the control shaft i geared thereto will assume complementary positions. As all these mechanisms are identical, the following description will be confined to only a single mechanism. Each push button |15 may be inserted in a section of the die-cast housing |31 formed by the horizontal flange |5| and the vertical ribs |13 o the housing located below the dial opening |33. Each button is provided with a recessed portion |33 formed so that it will telescope and fit snugly over the end 23| of a slide bar 233 provided with a right angle end portion 235 and also nt over the knuried head 231 of a locking shaft 233 which will be referred to later. The lower wall of the button |15, as best shown in Figure l2, is provided with a rectangular opening 2| I and a beveled surface 2|3 adjacent thereto (see Figure 6) so that a spring finger 2|5 (see Figure ll) which is fixed to the slide bar 233 by rivets 2|`| and provided with a downwardly projecting latch portion 2|3 and a beveled lip por tion 22| adjacent thereto will readily enter the opening 2li in the buttonwhen it is pushed on the bar 233 and hold it in the position shown in Figure 4. The button may be easily removed by exerting a slight upward pressure on the portion 2 i 3 of the spring finger 2 5 which extends through the opening 2| in the button |15.

Each slide bar 233 is supported for reciprocal, horizontal movement in the frame 23 by a slotted opening 223 in the front plate 2| through which the end 23| extends. The bar 233 is of increased width adjacent the slot 223 and has a blfurcated end portion comprising an upper leg 225 and a lower leg 221. These legs extend above and below the pinion portion |2| of the shaft ||5. Both the upper and lower legs are supported in slots 223 and 23| respectively in the rear plate i3. The lower leg 221 is provided with a downwardly extending hook portion 233 over which one end of a helical tension spring 235 is attached. I'he other end oi' the spring is attached to the front plate 2| and by this means the slide bar is urged outward so that an insulated abutment 231, which is formed by bending a portion of the upper extremity of the bar 203 outward at right angles thereto, is held in contact with the front plate 2| as best shown in Figures 2 and 3.

A pin 230 is riveted to the slide bar 203 at a point intermediate the support bearings and extends horizontally and at right anglesto the bar. The end 24| oi' this pin is of reduced diameter and serves as a bearing for a cam 233 rotatably mounted thereon. The cam 243 is provided with two lobes 245 and 201 with an arcuate portion 200 extending therebetween and into the lobe portions to constitute stops 25| and 253. A brake shoe member 255 is provided with a vertical groove 251 having a complementary arcuate surface in contact with the arcuate surface 230 of the cam. The shoe is held in irictional contact on the cam by a leaf spring 350 clamped between the slide bar 203 and the end 20| of a shoe support bar 203 which is riveted at 205 to the slide bar 203. Both the spring 250 and end 20| of the bar 203 extend into a horizontal groove 201 located in the shoe 255 to prevent the shoe from turning with the cam. The other end of the shoe support bar is riveted to the end 24| of the cam support pin 230 rsee Figures 2 and 3). The end 20| of the bar is provided with a threaded opening 200 through which the threaded end 21| of a hollow sleeve 213 extends and bears on the portion of the spring 250 in contact with the shoe 255 as shown best in Figure 3. This structure provides a means for locking the cam in any desired angular position with respect to the slide bar.

The other end of the sleeve 213 is supported for rotation in a drilled hole 215 in the right angle end portion 205 of the slide bar (see Figure 4). Rotation of the sleeve for locking the cam is accomplished by the locking shaft 200 having a knurled head 201, both of which have been previously referred to. The locking shaft 200 is supported for axial movement in the bore 211 of the hollow sleeve and is prevented from turning with respect thereto by a pin 20| pressed into a diametral hole near the inner end of the shaft 200. 'I'he ends oi "the pin 23| extend radially outward from the shaft and are supported for axial movement in axial slots 205 located diametrically opposite each other in the wall of the sleeve. A throat 200 is provided in the front face of the knurled head 201 so that the sleeve may be tightened with a screw driver to lock the cam tightly. A helical compression spring 201 is located in the bore 211 of the sleeve which tends to urge the shaft outward and serves to project the push button oli' the slide bar 203. The knurled head 201 is moved outward with respect to the sleeve 213 by the spring 201 so that it may be grasped by the hand for locking or unlocking the cam.

Located adjacent each slide bar 203 is an upper rack bar 200 and a lower rack bar 20|. 'Riese bars are supported for horizontal reciprocal movement in slots 203 in th baclrplate |3 and slots 205 in the front plate 2| .adjacent the slots 223, 220 and 23| supporting the slide bar 303. Both of these rack bars are provided with a rack portion 201 meshing with the pinion portion |-2I of the shaft at diametrically opposite points on its periphery. Each bar is provided with an abutment 200 spot-welded thereon and, so located with respect to the slide bar that they will be contacted by the lobes 235 and 231 of the cam carried thereon when it moves inwardly. Movement of the racks by the cam causes rotation of the shaft 5 in a direction depending upon the position of the abutments with respect to the cam and angular position of the cam with respect to the slide bar 203.

When the control shaft is to be rotated by the selector means, it is necessary to disconnect the clutch elements 00 and 03 which allows the shaft 41 to rotate with respect to the worm wheel 01. In order to do this the winding 00 must be connected to a source of current by an electrical switch indicated generally at 30| (see Figure 5). This switch consists of a contact 303 xed to a spring member 300 clamped between insulated members 305 and held on the side plate |1 by machine screws 301. Another contact 300 is riveted to an insulation strip 3| which is attached to the bent end 3|3 of a rod 3|5 by a rivet 3I1. The rod 3|5 is supported for rotation in alignment holes 3H' and 3|0 in the angular extensions 32| and 323 respectively on either end of the iront plate 2| of the selector frame 23 as shown in Figures 2 and 5. A helical torsion spring 323 located on the opposite rod end 325 and having one and hooked over the rod end and the other hooked over the extension 323, serves to normally hold the contact 300 in a spaced angular relation with respect to the contact 303 and maintain the straight portion 321 of the rod in contact with the beveled portions 320 formed on the inner end of the upper surface of the push buttons |15. The beveled portions 320 act as cams and initial inward movement of any push button lifts the portion 321 o! th rod and causes the switch contacts 303 and 30E to be closed.

The various electrical devices and control associated with the complete device are connected as shownin Figure 10 in which 320 is a battery, one side of which is grounded at 33| and the other side connected to a switch 333. This switch may be operated by a volume control knob 335 located on the housing member, as shown in Figure l, and is connected to the light |01 and switch 30| by the conductors |03 and 302 respectively.

The operation of the device is as follows: The switch 333, when closed by turning the volume control knob 335 from the oi! position, establishes a. circuit to ground through the indicator light bulb |01 and connects the contact o'i' the switch 30| to the battery 320. Turning the tu ing control knob |01 revolves the control shaft l by means of the worm 00, worm wheel 01 and clutch elements 00 and 33. The shaft is revolved by the gears," and lli and the upper and lower rack bars ,200 and 20| meshing with the shaft pinion portion |2| are moved linearly in opposite directions. The indicating needleI |3| is likewise moved by the belt |50 driven by the pulley |05 fixed to the shaft ||5 until a broadcasting station is received and identiied by the reading on the scale |31 adjacent the needle end |32. In order to cause the control shaft to be moved to this position by any one or the selector buttons |15. the following adjustments are made.

With the receiving set tuned to any identied station desired, any push button |15 is removed which allows the knurled head 201 to be moved outwardly by the spring 201 so that it may be turned to the left by hand or by a screw driver inserted in the throat 200 therein to unlock the cam 233. The slide bar 203 is pushed inwardly until the upper and lower lobes of the cam contact both of the abutments 299 on the rack bars 289 and 29| which causes it to assume an angular position with respect to the slide bar, depending upon the relative positions of the rack bars. The cam may be locked in this position by a screw driver while the slide bar is in its innermost position or by turning the knurled head upon the return of the slide bar and head to their normal outward positions. With the push button removed no movement of the rod portion' 321occurs when the slide bar is moved inwardly and the switch 30| which is actuated by this rod remains open which prevents disengagement of the clutch elements 69 and 93. The shaft H5 will be accordingly prevented from rotating by its geared connection with the tuning shaft which is held stationary by the engaged clutch elements and the worm gearing associated therewith while the cam is being set. This setting procedure is repeated for each slide bar cam and the removable identification tags may be lettered with the station call letters which the receiver will be tuned to upon subsequent inward movement ofthe individual slide bars.

The shaft H is moved to any one of these five positions by the cams in the following manner. Referring to Figure 3, it will be observed that if the slide bar 203 is moved inwardly a slight amount, the rod portion 321 will be raised by the beveled portion 329 on the upper inner edge of the button. This movement rocks the rod end 313 to close the contacts of the switch 30| and energizes the coil 89 which disengages the clutch elements 69 and 93, rendering the control knob I01 ineffective for rotating the shaft 4l. The control shaft i may now be moved by its connection to the shaft 41 which is rotated by the gear 11 meshing with the gear il I fixed to the shaft H5. Rotation of these parts is resisted by the residual drag between the disengaged clutch elements, inherent friction of the moving parts and the restraint on the control shaft which may be varied by the end thrust adjusting means 5 located on one end of the shaft I.

Referring to Figure 3, it will be observed that when the slide bar 203 is moved toward the shaft iii, the cam lobe 241 contacts the abutment 299 on the lower rack bar 29! moving it inward. The shaft H5 will be rotated clockwise by the rack bar until the upper cam lobe 245 contacts the abutment 299 on the upper rack bar 289. When this occurs the movement of the shaft rack bars and slide bar ceases. The shafts IIS and I are retained in this position by bearing friction and the slide bar is returned to its original positien by the spring 235. The switch 30i is opened when this takes place and the clutch elements are reengaged by the spring 85.

With this selector mechanism the control shaft I may be rotated in either direction to one of a plurality of angular positions and each mechanism my be adjusted to change any of these positons by unlockilg the cam carried on the slide bar and tuning another station by means of the control knob. This changes the angular position of the shaft il! and the cam may be moved with reference to the slide bar by pushing the bar inward. The cam is then locked and the shaft will be moved to this new position whenever the slide bar is pushed in.

We claim:

1. In an automatic indexing and tuning mechanism for radio communication devices comprising. a control shaft. reciprocable means operatively connected to the control shaft, actuating means for said reclprocable means to rotate said control shaft in either direction to a predetermined angular posltion, rotatable means for rotating said control shaft to any one of a plurality of angular positions, clutch means normally connecting said rotable means to said control shaft and means for disconnecting said clutch means. said last named means including control means engageable by and operable by said actuating means.

2. In an automatic indexing and tuning mechanism for radio communication ,devices comprising, a control shaft, reciprocable means operatively connected to said control shaft, reciprocable actuating means for said recoprocable means to rotate said control shaft in either direction to a predetermined angular position, rotatable means for rotating said control shaft in either direction to any one of a plurality of angular positions, clutch means normally connecting said rotatable means to said control shaft and means for disconnecting said clutch means, said last named means including control means engageabie by and operable by said reciprocable actuating means.

3. In an automatic indexing and tuning mechanism for radio communication devices comprising, a control shaft. reclprocable means operatively connected to said control shaft, reciprocable actuating means for said reclprocable means movable in one direction to rotate said control shaft in either direction to a predetermined angular position, means normally blaslng said actuating means to its inoperative position, rotatable means for rotating said control snaft to any one of a. plurality or' angular positions, said retable means having irreversible characteristics, clutch means normally connecting said rotatable means to said control shaft and means for disconnecting said clutch means, said last named means including control means engageable by and operable by movement ol said reclprocable actuating means from its inoperative position.

e. In an automatic indexing and tuning mechanism for radio communication devices comprising, a control shaft, reciprocable means operatlvely connected to the control shaft, reciprocable actuating means for said reciprocable means including adjustable means for contacting said reciprocable means whereby said control shaft may be rotated to any one of a plurality of predetermined angular positions, rotatable means for rotating the control shaft in either direction and holding said shaft in any one of a plurality of angular positions, clutch means normally connecting said rotatable means to said control shaft and means for disconnecting said clutch means. said last named means including switching means engageable by and controlled by said reciprocable actuating means.

5. In an automatic indexing and tuning mechanism for radio communication devices comprising. a control shaft, reciprocable means operatively connected to said control shaft, reciprocable actuating means for said reciprocable means to rotate said control shaft to any one of a. plurality of predetermined angular positions, said actuating means including a member angulariy adjustable with respect thereto adapted to be moved thereby into contact with said reciprocable means. locking means for said member, removable means adapted to be supported on said actuating means and resilient means for retaining said removable means thereon, rotatable means 6 asuma for rotating said control shaft in either direction to any one of a plurality of angular positions, a clutch normally connecting said control shaft to said rotable means, and means for disconnecting said clutch, said means including switching means engageable by said removable means and controlled by initial movement thereof when retained on said reciprocable actuating means.

6. In an automatic indexing and tuning mechanism for radio communication devices comprising, a control shaft, reciprocable means operatively connected to said control shaft, reciprocable actuating means for said reciprocable means to rotate said control shaft to any one of a plurality of predetermined angular positions. said actuating means including an angularly adjustable member adapted to contact said reciprocable means, telescopic means for locking said angularly adjustable member in any one of a plurality of angular positions on said actuating means, said telescopic means normally biased to project beyond said actuating means, a removable push button adapted to be supported on said actuating means, resilient means retaining said push button thereon and depressible to release said push button therefrom, said push button when retained on said actuating means serving to enclose and hold said telescopic locking means retracted, rotatable means for rotating said control shaft in either direction to any one of a plurality of anguiar positions, clutch means normally connecting said control shaft with said rotatable means, means for disconnecting said clutch means and control means for said last named means engageable by said push button and controlled by initial movement of said push button when retained on said actuating means.

'7. In an automatic indexing and tuning mechanism for radio communication devices comprisins. a control shaft, reciprocable means operatively connected to said control shaft, actuating means for said reciprocable means to rotaie said shaft in either direction to a predetermined angular position, said means including removable means and manually operable retaining means therefor to release said removable means, rotatable means for rotating said control shaft in either direction to any one of a plurality of positions, a clutch normally connecting said control shaft to said rotatable means and including an electro-magnetic winding adapted when energized to disconnect said clutch and a control switch connected electrically to said electromagnetic winding to control the energization thereof, said switch actuated by said removable means when retained on and initially moved by said actuating means.

8. In an automatic indexing and tuning mechanism for radio communication devices comprising. a control shaft, a plurality of motion transmitting means operatively connected to said shaft, actuating means for each of said motion transmitting means, each of said actuating means being radially movable with respect to said shaft and comprising adjustable means capable of being moved into contact with one of said motion transmitting means to rotate said control shaft in either direction to any one oi' a plurality of preselected angular positions, telescopic locking means for said adjustable means including biasing means to extend said locking means for manual operation thereof, a removable button mounted on said actuating means to enclose and hold said telescopic locking means collapsed and manually releasable retaining means for retaining saidv button on said actuating means, a member supporting all the above apparatus provided with an aperture through which all of said buttons project for manual operation of each actuating means and the locking means associated therewith.

9. In an automatic indexing and tuning mechanism for radio communication devices comprising, a control shaft, a plurality of motion transmitting means operatively connected to the control shaft, actuating means for each of said motion transmitting means movable at right angles with respect to said control shaft, each of said actuating means comprising adjustable means capable of movement into contact with one of said motion transmitting means to rotate said control shaft in either direction to any one of a, plurality of preselected angular positions, telescopic locking means for said adjustable means including biasing means to extend said telescopic means for manual operation thereof, a removable push button mounted on said actuating means for manual operation thereof, manually releasable retaining means for retaining said button on said actuating means, said push button when so retained enclosing and holding said telescopic locking means in a collapsed position and biasing means for said actuating means normally holding said adjustable means out of contact with said associated motion transmitting means, means for rotating said tuning shaft in either direction and holding said shaft in any one of a plurality of angular positions including an actuating knob, and a`clutch normally connecting said control shaft with said rotatable means, said clutch including an electromagnet adapted when energized to disconnect said clutch, switch means electrically connected to said electromagnet for controlling the energization thereof, actuating means for said switch operable by any one of said push buttons when retained on its actuating mechanism, and a housing member supporting all of the above apparatus having apertures through which each of said buttons and said knob projects for manual operation.

10. In electrical apparatus comprising a movable tuning unit, in combination, a driving member for moving said tuning unit, connecting means for coupling said member to said tuning unit. means for indicating the relative position of said tuning unit, connecting means for coupling said indicating means to said driving member, manual means for moving said driving member, clutch means for coupling said manual means to said driving member for manual operation, and release means operating on said clutch means for uncoupling the said manual means from said driving member, and means operable while said manual means is uncoupled for moving said driving mem-A ber to a predetermined setting.

l1. In a device as per claim 10 in which said means operable when said manual means is uncoupled comprises a rotatable member coupled to said driving member and a plurality of plunger-operated cams, each adapted to rotate said rotatable member over a predetermined adinstable angle o! rotation.

12. In a radio control device. a rotatable control shaft, a plurality of longitudinally movable driving and stopping means operably connected to the shaft, means projecting from each longitudinally movable means at an intermediate point in its length and a second longitudinally movable means engaging the projecting means to cause the driving and stopping means to move and rotate the shaft in either direction of a. predeterin its length. and a plurality of further longitumined angular position. dinally movable means each engaging a pair of 13. In a radio eontrol device, a. rotatable oonthe first-named longitudinally movable means to trol shaft. a plurality ot longitudinally movable individually rotate the shaft to different prededriving and stopping means operably connected 5 termined angular positions.

to the shaft. means projecting from each longi- BERTRAM A. SCHWARZ. tudinally movable means at an intermediate point LUDWIG J. FI 

